Device for locking a door element in an opening to a space

ABSTRACT

The present invention relates to a device for locking a door element ( 1   a ) in an opening to a space. The device comprises an operating member ( 2 ) arranged outside this space, which member ( 2 ) is arranged to allow, by a motion transmission mechanism, displacement of a locking bar ( 6 ), arranged inside the space, between a first position when the locking bar ( 6 ) allows an opening of the door element ( 1   a ) and a second position when the locking bar ( 6 ) connects the door element ( 1   a ) to a second element ( 1   b ) such that opening of the door element ( 1   a ) is prevented and a lock ( 3 ) allowing locking of the locking bar ( 6 ) in said second position. A protective housing ( 5 ) is arranged to encase the locking bar ( 6 ) and the parts of the lock ( 3 ) and the motion transmission mechanism that are arranged inside the space.

TECHNICAL FIELD OF THE INVENTION AND PRIOR ART

The present invention relates to a device for locking at least one doorelement in an opening to a space, wherein the device comprises anoperating member arranged outside the space, which is arranged to allow,by a motion transmission mechanism, displacement of a locking bar,arranged inside the space, between a first position when the locking barallows an opening of the door element and a second position when thelocking bar connects the door element to a second element such that anopening of the door element is prevented and a lock allowing locking ofthe locking bar in said second position.

By a door element is meant a door, cover or the like which may be usedfor closing an opening to a space of an arbitrary kind. In many cases,locking devices for door elements usually are countersinked in recessesprovided in the door element. Such recesses result in that the originalthickness of the door element and thereby the strength decreases in thatarea, which is utilised by thieves.

Other kinds of locking devices are arranged outside the door element.Such locking devices may, for example, comprise a locking bar which hasone end attached to the door and a second end, which may be fixedlylocked to a rigid wall element adjacent to the door, for example, bymeans of a pad lock. Such locking devices may easily be broken to open,for example, by a hydraulic cutter which has the capacity to cut ofsteel with a thickness of up to 15 mm. Alternatively, one end of a heavywire may be attached to the locking bar and the second end to a vehicle,whereafter the vehicle may pull out the locking bar.

Locking devices, which substantially have its locking mechanism arrangedon the inside of a door element, provides the best protection againstburglary from the outside. However, these locking devices do noteliminate the risk that a thief hides inside or enters a space, which,for example, may be a storage space or a container. Thereafter, thethief may dismount the locking device from the inside. Alternatively,the thief may enter, for example, a storage room, via a window, with thepurpose of from the inside dismounting the locking device to facilitatethe possibility ton take out the stolen goods.

FR 2 533 961 shows a locking device having a locking mechanism providedon the inside of a door. The rotary motions of an operating member onthe outside of the door are transmitted, in this case, to a rotarymotion of a gear wheel on the inside of the door. The rotary motions ofthe gear wheel are transmitted to a displacement motion of a lockingbar, via a toothed surface provided thereon, between a door blocking anda not blocking position. A lock is arranged to lock the locking bar inthe blocked position. In order to control the displacement motions ofthe locking bar, metal plates are provided, which are so shaped thatthey form rectangular channels in which the locking bar is displaceablyprovided. One such metal plate is arranged on the inside of the door andanother on the inside of an adjacent wall. In order to attach theseinwardly provided metal plates, corresponding external metal plates areprovided on the outside of the door and on the outside of said adjacentwall. These external metal plates comprise fixed soldered boltsextending through the door and the adjacent wall and through holes inthe internal metal plates. Thereafter, nuts are provided on the threadedportions of the bolts in order to fix the internal metal plates to theinside of the door and the adjacent wall and thereby said guide channelof the locking bar. For a thief hidden at the inside of the door, it isvery simple to screw off said nuts and to disengage the internal metalplates and thereby the locking bar. Furthermore, the gear wheel and thelock are unprotected against attacks from the inside of the door.

SUMMARY OF THE INVENTION

The object of the present invention is to provide a device for locking adoor element such that it becomes very difficult for a thief to forcethe locking device both from the outside and from the inside of the doorelement.

This object is achieved by the initially mentioned device which ischaracterised in that it comprises a protective housing which isarranged to encase the locking bar and the parts of the lock and themotion transmission mechanism that are arranged inside the space. Bysuch a protective housing covering sensible parts of the device, attackson these parts are considerably more difficult. Preferably, theprotective housing is manufactured of thick hardened steel. Anotheradvantage by protecting said substantially moveable parts of the device,is that one prevents the internal locking mechanism from being blockedby unfixed goods provided in the space, which may be the case, forexample, in a container.

According to a preferred embodiment of the present invention, theprotective housing is attached to at least one internal wall surface ofthe space. Thereby, the protective housing may obtain an uncomplicatedand stable fixation. Preferably, the protective housing is attached tosaid internal wall surface by means of a non-dismountable attachmentmeans. Thereby, it is essentially more difficult for a thief to dismountthe protective housing from the inside in order to reach and break openthe locking mechanism. Such non-dismountable attachment means may bebolts having heads which preferable are countersinked in a mounted stateand having such a shape that they are difficult to grip. Suchnon-dismountable attachment means may also comprise rivets or welding.

According to another preferred embodiment of the present invention, theprotective housing comprises a channel in which the locking bar isdisplaceably provided. Such a protective housing thereby also may workas guiding element to the locking bar. The protective housing maycomprise at least two separate parts and that a first part of theprotective housing is attached to an internal wall surface and that thesecond part of the protective housing is attached to an internal wallsurface of said second element. Since the locking bar extends betweenthe door element and the second element, it is suitable that theprotective housing is arranged as two separate parts. However, the partsof the protective housing will lie close to each other in the closedposition of the door element so that they form a continues channel sothat the locking bar may be displaced to its second position.Alternatively, the protective housing may be provided as a single part,which is attached to the door element or the adjacent element. Thesecond element may comprise a second openable door element or a rigidwall element. When double door elements are used, the two door elementsmay be locked together by the locking bar. For a single door element itis suitable that the locking bar locks the door element in relation toan adjacent rigid wall element.

According to another preferred embodiment of the present invention, itcomprises coupling means, which is arranged to restrict the force, whichthe operating member, via the motion transmission mechanism, is allowedto transmit to the locking bar. Thereby, the risk is prevented that athief by suitable tools from the outside provides a such a heavy forceonto the operating member that the locking bar is displaced and deformsthe locking mechanism. Such coupling means may comprise a suitable kindof safety clutch. Advantageously, the motion transmission mechanism isarranged to transmit a rotary motion of the operating member to areciprocal displacement motion of the locking bar. Preferably, theoperating member is a rotateable wheel or crank arranged on the outsideof the door element. The operating member is connected to a suitablemotion transmission mechanism which transforms the rotary motion of theoperating member to a reciprocal motion of the locking bar between saidfirst and second position. Preferably, the motion of the locking bar islinear.

According to another preferred embodiment of the present invention, thelocking bar has a front portion provided in a displacement direction,said front portion comprises at least one chamfering. By such achamfering, the risk is eliminated that the locking bar tilts and jamsduring the displacement motion in the channel. Especially when theprotective housing consists of two pieces and the channel is divided,such a chamfering brings about that the parts of the channel are centredto a desired position in relation to each other during the displacementmotion of the locking bar.

According to another preferred embodiment of the present invention, thelock comprises a bolt, which is insertable in a recess in the lockingbar in order to lock the locking bar in said second position.Preferably, such a lock comprises a lock body extending through thedoor. On the outside of the door element, a key activates the lock sothat the bolt, which is provided on the inside of the door, is displacedin or out of said recess. Preferably, the lock is a 9-lever tumblerlock. Such a lock is a high security lock, which is approved to be usedin safes. The key of the lock is protected against an unauthorisedcopying. Furthermore, the lock has a barrier, which prevents insertionof optical means for photographing the inside with the purpose ofmanufacturing an unauthorised key.

According to another preferred embodiment of the present invention, thedevice comprises a protecting plate arranged outside the space forcovering at least a part of a slit provided between the door element andsaid element, which part of the slit the locking bar internally extendspassed in its second position. Preferably, such a protecting plate hasan extension along the slit, which at least corresponds to the width ofthe locking bar. By such a protecting plate, it is made more difficultfor a thief to insert a cutting tool in the slit with the purpose to cutoff the locking bar.

BRIEF DESCRIPTION OF THE DRAWINGS

In the following, preferred embodiments of the invention are describedas examples with reference to the attached drawings, in which:

FIG. 1 shows, from the outside, two pivotally arranged door elementshaving a locking device according to the present invention,

FIG. 2 shows, from the inside, said door element having a locking deviceaccording to a first embodiment,

FIG. 3 shows, from the inside, said door element having a locking deviceaccording to a second embodiment and

FIG. 4 shows, from the inside, said door element having a locking deviceaccording to a third embodiment.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION

FIG. 1 shows from the outside first 1 a and second 1 b pivotallyarranged door elements. Said door elements 1 a, b, may, for example, beused to cover and lock an opening to, for example, a space in acontainer. A turnable operating member 2 is arranged on the outside ofthe door element 1 a by which a user is allowed to operate a lockingmechanism arranged on the inside of the door element 1 a, 1 b. Theoperating member 2 may also be used as a handle in order to open andclose the door element 1 a. The second door element 1 b comprises a lock3 of which a front portion having a keyhole is visible from the outsideof the door element 1 b. A protecting plate 4 is fixedly provided on theoutside of the door element 1 b by a suitable attachment means. Theprotecting plate 4 has an extension so that it covers a part of the slitbetween the door elements 1 a, 1 b. The object of the protecting plate 4is to make it more difficult to insert cutting tools in the slit inorder to cut off the internally provided locking mechanism. By the factthat the locking mechanism is located substantially on the inside of thedoor elements 1 a, 1 b, it is very difficult for a thief to break openthe door elements 1 a, 1 b in a locked state. By dashed lines in FIG. 1is shown a protective housing 5 arranged on the inside of the doorelements 1 a, 1 b, which is arranged to protect the locking mechanismarranged on the inside of the door elements 1 a, 1 b.

FIG. 2 shows from the inside of the space the first 1 a and the second 1b pivotally arranged door elements. The protective housing 5 is arrangedto encase that part of the locking mechanism, which is providedinternally of the space. The protective housing 5 comprises a first part5 a which is attached to the inside of the door element 1 a and a secondpart 5 b which is attached to the inside of the door element 1 b. Theprotective housing 5 comprises a base plate with which it is attached tothe inside of the respective door element 1 a, 1 b by special bolts.Such special bolts have a head shape, which minimises the possibility toget a grip of them with tools. Alternatively, other non-dismountableattachment methods may be used, for example, the base plates may bewelded or attached by rivets to the inside of the door elements 1 a, 1b. Except for the base plate, the protective housing 5 comprises aportion disclosing an inner cavity in which the locking mechanism isencased. This cavity comprises in this case a channel having arectangular cross sectional profile. Certainly, the channel may have anarbitrary cross sectional profile adapted to the cross section of alocking bar 6 which is displaceably provided in the channel. The lockingbar 6 is also shown as a separate unit in FIG. 2. The locking bar 6 isdisplaceable between a first position where the locking bar 6 only islocated in a channel part, which belongs to the first part 5 a of theprotecting housing and a second position where the locking bar 6 extendsinto a channel part, which belongs to the second part 5 b of theprotective housing. Thereby, the locking bar 6 connects the doorelements 1 a, 1 b to each other so that they cannot be opened. Thedisplacement of the locking bar 6 is obtained by a turning of theoperating member 2, which is placed on the outside of the door element 1a. The turning motions of the operating member 2 are transmitted to alinear displacement motion of the locking bar 6 by a motion transmissionmechanism. The motion transmission mechanism comprises a shaft 7connected to the operating member 2 which transmits the turning motionof the operating member 2 to a gear wheel 8. Between the shaft 7 and thegear wheel 8 a safety clutch is provided. The rotary motion of the gearwheel 8 is transmitted, by a toothed pattern 9 provided to the lockingbar 6, to a linear reciprocal motion of the locking bar 6. The lockingbar 6 comprises a recess 10 located straight below the lock 3 in thesecond position of the locking bar 6. The lock 3 comprises adisplaceable bolt 11, which is insertable in the recess 10 in order tolock the locking bar 6 in said second position. In order to position thelocking bar 6 in said second position, the locking bar 6 comprises astop lug which is arranged to get into engagement with a stop member 13when the locking bar 6 reaches the second position. Consequently, in alocked position the locking bar 6 is not operable with the operatingmember 2. By the safety clutch, which preferably is a friction clutch,the force the operating member 2 may provide to the locking bar 6 isrestricted. Thereby, the lock 3 cannot be deformed by providing a veryheavy force on the locking bar 6 by means of the operating member 2. Theprotective housing 5 comprises also a part 5 c which is arranged toencase that part of the lock 3 which is located on the inside of thedoor element 1 b. Finally, the protective housing 5 comprises a part 5d, which encases the gear wheel 8. Consequently, the protective housing5 encases all the moveable parts of the locking mechanism which arearranged on the inside of the space which makes it very difficult tomanipulate or deform the locking mechanism from the inside and theoutside of the door elements 1 a, 1 b. The front portion of the lockingbar 6 has chamfering portions 14. By such chamferings 14, the risk thatthe locking bar 6 is tilted and jammed during the displacement motion inthe channel is eliminated. Especially when the protective housing 5 isshaped into two parts and the channel divided, such chamfering 14 workto control the locking bar in the receiving channel part during thedisplacement motion of the locking bar 6. This is a great help if thedoor elements 1 a, 1 b have been warped.

FIG. 3 shows an alternative embodiment of the motion transmissionmechanism of the locking mechanism. In this embodiment the turningmotions of the operating member 2 are transmitted, via the shaft 7, to afirst pulley 15. The pulley 15 transmits its rotary motion to a cord 16.The cord 16 forms an endless loop, which except for said first pulley 15also extend around the periphery of a second pulley 17. The secondpulley 17 is fixedly carried in the protective housing 5. The cord 16 isfixedly attached in the locking bar 6 in an attachment 18. When thepulley 15 rotates, the cord 16 is displaced along said endless loop.Thereby, the attachment 18 in the locking bar 6 is displaceable betweenthe positions of the pulleys 15, 17 and thereby brings the locking bar 6between its first and second position. The locking bar 6 is partlyhollow so that it may be moved to and back pass the second pulley 17 andpartly encase the cord 16. Except that the operating member 2 in FIG. 3has been moved somewhat sideways, the remaining parts of the lockingmechanism correspond to the ones shown in FIG. 2. Alternatively, thepulleys 15, 17 may be replaced by a chain wheel and the cord 16 by achain.

FIG. 4 shows a further alternative embodiment of the motion transmissionmechanism of the locking mechanism. In this embodiment, the turningmotions of the operating member 2 are transmitted, via a flexible shaft7′, to a threaded rod 18. A nut 19 is fixedly provided in the rear endof the locking bar 6. By the rotary motion of the threaded rod 18, thenut 19 and the locking bar 6 obtains a reciprocal linear motion when theoperating member 2 is turned. The locking bar 6 is also here partlyhollow in order to allow the insertion of the threaded rod 18 during itsdisplacement motion. The remaining parts of the locking mechanism inFIG. 4 correspond to the ones shown in 3.

As a further alternative, the motion transmission mechanism may comprisea worm gear for transmitting the turning motion of the operating member2 from the shaft 7 to, for example, a threaded rod 18.

Preferably, the lock 3 shown in the figures comprises a 9-lever tumblerlock of the brand FAS. This lock is a high safety lock, which isapproved for safes. Furthermore, the lock 3 has a built-in protection,which prevents insertion of fibre optical equipment. Thereby,photographing of the lock internally via the keyhole in order to producea false key is prevented. The invention is not restricted to theembodiments described in the figures, but may be varied freely withinthe scope of the claims.

What is claimed is:
 1. A device for locking at least one door element inan opening to a space, wherein the device comprises an operating memberarranged outside the space, which member is arranged to allow, by amotion transmission mechanism, displacement of a locking bar, arrangedinside the space, between a first position when the locking bar allowsan opening of the door element and a second position when the lockingbar connects the door element to a second element such that an openingof the door element is prevented and a lock allowing locking of thelocking bar in said second position, characterized in that a protectivehousing is arranged to completely encase the locking bar and all theparts of the lock and the motion transmission mechanism that arearranged inside the space.
 2. A device according to claim 1,characterized in that the protective housing is attached to at least oneinternal wall surface of the space.
 3. A device according to claim 2,characterized in that the protective housing is attached to saidinternal wall surface by non-dismountable attachment means.
 4. A deviceaccording to claim 2, characterized in that the protective housingcomprises a channel in which the locking bar is displaceably provided.5. A device according to claim 1, characterized in that the protectivehousing comprises at least two separate parts and that a first part ofthe protective housing is attached to an internal wall surface of thedoor element and that a the second part of the protective housing isattached to an internal wall surface of said second element.
 6. A deviceaccording to claim 1, characterized in that said second elementcomprises a second openable door element or a rigid wall element.
 7. Adevice according to claim 1, characterized in that the device comprisescoupling means restricting the force, which the operating member,through the motion transmission mechanism, is allowed to transmit to thelocking bar.
 8. A device according to claim 1, characterized in that themotion transmission mechanism is arranged to transmit a rotary motion ofthe operating member to a reciprocal displacement motion of the lockingbar.
 9. A device according to claim 8, characterized in that the lockingbar has a front portion provided in a displacement direction, said frontportion comprises at least one chamfering.
 10. A device according toclaim 1, characterized in that the lock comprises a displaceable boltwhich is insertable in a recess in the locking bar in order to lock thelocking bar in said second position.
 11. A device according to claim 1,characterized in that the lock comprises a 9-lever tumbler lock.
 12. Adevice according to claim 1, characterized in that the device comprisesa protecting plate arranged outside the space in order to cover at leasta part of a slit provided between the door element and said element,which part of the slit the locking bar internally extends passed in asecond position.